Muffler with baffles formed as chordal flanges



J. .P. MARX 3,313,373

MUFFLER WITH BAFFLES FORMED AS CHORDAL FLANGES April 11, 1967 2 Sheets-Sheet 1 Filed Jan. 11. 1965 Q mw INVENTOR. Joseph P Marx ZZWJK J. P. MARX April 11, 1967 MUFFLER WITH BAFFLES FORMED AS CHORDAL FLANGES Filed Jan. 11, 1965 2 Sheets-Sheet 2 INVENTOR. Jase 2h F2 Mar-x United States Patent 3,313,373 MUFFLER WITH BAFFLES FORMED AS CHQRDAL FLANGES Joseph P. Marx, Hartford, Wis., assignor to Midas International Corporation, Chicago, 11]., a corporation of Illinois Filed Jan. 11, 1965, Ser. No. 424,559 13 Claims. (Cl. 181-69) The invention relates to improvements in inufilers for internal combustion engines and is more particularly concerned with the novel construction and assembly of a device for muffling expanding and noise producing exhaust gases without setting up detrimental back pressure.

The invention, more particularly, resides in a muflier which is so constructed as to provide a main straight through gas duct or passageway and sound deadening means in communication therewith through perforations and openings in the passageway, the openings each having a novelly formed and arranged flange associated therewith that lies across the path of the stream of gases flowing through the gas duct in such manner as to cause deflection and breaking up of the sound waves into a multitude of turbulated streams, all of which features combine to deaden the explosive peaks of the sound waves.

The invention also contemplates the arrangement of an inlet fitting to the gas duct that is disposed to direct inflowing gases toward and against the wall of the duct preferably in the area containing the flanges so as to further increase the turbulance imparted to the gases flowing therethrough.

It is therefore an object of the invention to provide a muffler embodying the structural characteristics above noted. 7

Another object is to provide, in a mufller, a cylindrical passageway for exhaust gases which is formed with novel viding a uniform duct for the passage of gases therethrough. A casing 12, including end walls .13, is formed about the cylinder 11 to form a chamber 14 between the cylinder and casing wall. Inlet and outlet fittings 15 and 16 respectively, are joined firmly, as by welding, to the ends of cylinder 11 and preferably at least the inlet fitting 15 is disposed at a slight angle to the longitudinal axis of the conduit for a purpose to be explained presently.

The cylinder 11 is formed with circumferentially elongated openings 17 that are longitudinally spaced apart uniformly in two diametrically opposed rows. Each of these openings has, integral with one edge, a flange 18 that projects into the cylinder and lies in a plane perpendicular to its longitudinal axis. These flanges are formed with a straight edge 18a and they are preferably of a width equal to about one-seventh of the diameter of the cylinder 11. The cylinder also has a plurality of longitudinal rows of mutually spaced apart apertures or ports 19 arranged between the rows of openings 17.

Preferably, the cylinder 11 is made up of two like longitudinal halves joined permanently together in seams 21.

sound wave interrupting flanges that lie perpendicular to the longitudinal axis of the passageway.

Another object is to provide inlet means for directing exhaust gases into a gas duct in a manner to greatly facilitate turbulating of such gases as they enter said duct.

Another object is to provide a muffler with a cylindrical gas passageway having a multitude of openings therein of different sizes, all effective to deaden the explosive peaks of the sound waves of gases passing therethrough.

Another object is to provide a muffler of the character referred to which is simple and economical to construct, eflicient in operation, and adaptable for use with different types of internal combustion engines.

The structure by means of which the above noted and other objects and advantages of the invention are attained will be described in the followingspecification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in

which:

FIG. 1 is an elevational View, partly broken away, of a muffler embodying the invention.

FIG. 2 is an enlarged fragmentary longitudinal central sectional view of the muffler.

FIG. 3 is a diametrical sectional view, taken substantially on line 33 of FIG. 2.

FIG. 4 is a fragmentary enlarged view of the inside surface of the cylindrical conduit.

FIG. 5 is a fragmentary longitudinal sectional view of a muffler of modified construction.

FIG. 6 is a fragmentary longitudinal sectional view of another modified form of muffler.

Referring to the exemplary disclosures of the invention as shown in the accompanying drawings, and particularly to the structure depicted in FIGS. 1 through 4, the muffler comprises an inner cylinder or conduit 11 pro In the FIG. 2 illustration, the halves are joined together in such manner that the flanged openings 17 in each row of openings are diametrically opposed and the flanges 18 thereon are contained on the trailing or rear edges thereof. By reversing the conduit assembly in the casing at the time of manufacture, the flanges can be located on the leading edges of the openings 17, while upon reference to FIG. 5, the halves can be reversed end to end, at assembly, so that the flanges 18 on one row of openings 17 are on the leading edges whereas the flanges 18 on the other row of openings 17 are on the trailing edges. In the FIG. 6 disclosure, the halves are connected so that the openings in one row of openings is longitudinally offset from the openings 17 in the opposed row of openings. Obviously, the flanges 18 on these openings can be on the trailing edges as shown, on the leading edges, or on the trailing edges of the openings in one row and on the leading edges of the openings in the other row, depending upon the mode of assembly. As will be better understood as the description proceeds, different sound effects can be obtained by the several different arrangements of the openings and flanges.

The chamber 14 is filled or substantially filled with a porous gas pressure absorbing and sound absorbing material 22, such as mineral fiber, metallic wool or any other material that is non-inflammable including ex panded vermiculite. Preferably, the material is packed to lie away from the area of the cylinder having the openings 17 therein, such as by providing a tunnel or void 23 therein.

In use, exhaust gases entering through the inlet fitting 15 will initially be directed toward the wall of the conduit, preferably in the area of one row of flanges 18 by reason of the angular inclination of the inlet fitting 15. The gases, upon striking these flanges which are perpendicular to the axis of the conduit, is turbulated and repeatedly thrust back and forth across the conduit diameter as it advances toward successive flanges so as to effectively interrupt and break up sound waves in the main stream therein. Further, deadening of sound waves is effected by the passage and expansion of considerable quantities of such gases into and out of the tunnels 23, when such tunnels are provided. In the instance of no tunnels being present, the gases permeate the porous absorbent material and expand, entering same through the openings 17, and also through the ports 19, and bounce back irregularly through said openings and ports into the main stream of gases in the cylinder 11. The perpendicular disposition of flanges 18 is highly effective to cause maximum disturbance of the sound waves when Patented Apr. 11, 1967 louvers for gas stream disturbance. In instances where the louvers are inclined in the direction of flow the turbulation is nominal because the gases tend to slip past the louvers and continue to travel in the general direction of the main stream. When the louvers are inclined in a direction opposed to the direction of flow, they produce a reverseflow that increases back pressure in the gas duct. In the present disclosure, the perpendicular flanges cause an abrupt violent disturbance of the gases laterally thus more effectively breaking up sound waves in the main stream, all without setting up detrimental back pressure.

Although I have described preferred embodiments of my invention, in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the structure may be modified or changed without departing from the spirit or scope of the invention. Accordingly, I do not desire to be restricted to the exact construction described.

I claim:

1. A mufiler comprises a cylinder having a substantially uniform gas duct extending therethrough, a closed casing formed about said cylinder to form a chamber between the cylinder and easing, said cylinder having circumferentially spaced apart longitudinal rows of circumferentially elongated openings therein, a sound absorbing material substantially filling said chamber, and a plurality of chordal flanges one integral with a longitudinal edge of each opening, said flanges lying in planes perpendicular to the cylinder axis and extending into the interior of said cylinder.

2. The rnufller recited in claim 1, in which the openings are arranged in two longitudinal rows diametrically opposed to one another.

3. The mufller recited in claim 1, in which the openings are arranged in two longitudinal rows diametrically opposed toone another and the remaining area of the cylinder is perforated.

4. The mufller recited in claim 1, in which the openings are arranged in two longitudinal rows diametrically opposed to one another and the openings in one row are diametrically aligned with the openings in the other row.

5. The mufller recited in claim 1, in which the openings are arranged in two longitudinal rows diametrically opposed to one another and the openings in one row are longitudinally offset from the openings in the other row.

6. The muffler recited in claim 1, in which an inlet fitting is carried on the inlet end of said cylinder, said fitting being disposed at an angle to the axis of said cylinder so as to direct inflowing gases against the wall of said cylinder.

7. The mufller recited in claim 1 in which an inlet fltthe inlet end of said cylinder, said'.

ting is carried on fitting being disposed at an angle to the axis of said cylinder so as to direct inflowing gases against that portion of the cylinder wall having a row of flanged openings therein.

8. The muffler recited in claim 1, in which the sound absorbing material is formed to provide a void in the region of each opening.

9. The mufl ler recited in claim 1, in which the sound absorbing material is formed to provide longitudinal voids one in flow communication with each row of openings.

10. A mufller comprising a cylinder having a substantially uniform gas duct extending therethrough and an inlet and outlet at opposed ends, a closed casing formed about said cylinder to form a chamber between the cylinder and casing, said cylinder having circumferentially spaced apart longitudinal rows of circumferentially elongated openings therein, a sound absorbing material sub-- stantially filling said chamber, said material being formed to provide longitudinal channels one in flow communication with the openings in each row of openings, a chordal flange integral with an edge of each opening, said flanges extending perpendicular into the interior of the cylinder.

11. The muffler recited in claim 10, in which the flanges are on the forward edges of the openings.

12; The muffler recited in claim 10, in which the flanges are on the rear edges of said openings.

13. The rnufller recited in claim 10, in which the flanges on the openings in one row of openings are on the forward edges thereof and the flanges on the openings in the other row of openings are on the rear edges thereof.

References Cited by the Examiner UNITED STATES PATENTS 1,991,748 2/1935 Johnson 181-70 X 1,993,397 3/1935 Berg et a1. 181-48 2,523,260 9/1950 Campbell 18150 2,828,830 4/1958 Clark 181-70 X 3,209,861 10/1965 Whitney 181-6l X FOREIGN PATENTS 988,370 4/ 1951 France.

1,074,071 3/ 1954 France.

RICHARD B. WILKINSON, Primary Examiner.

R. S. WARD, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,313,373 April 11, 1967 Joseph P. Marx It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the heading to the printed specification, lines 5' n "a corporation of Illinois" read a corporation of Delaware Signed and sealed this 14th day of November 1967.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer 

1. A MUFFLER COMPRISES A CYLINDER HAVING A SUBSTANTIALLY UNIFORM GAS DUCT EXTENDING THERETHROUGH, A CLOSED CASING FORMED ABOUT SAID CYLINDER TO FORM A CHAMBER BETWEEN THE CYLINDER AND CASING, SAID CYLINDER HAVING CIRCUMFERENTIALLY SPACED APART LONGITUDINALLY ROWS OF CIRCUMFERENTIALLY ELONGATED OPENINGS THEREIN, A SOUND ABSORBING MATERIAL SUBSTANTIALLY FILLING SAID CHAMBER, AND A PLURALITY OF CHORDAL FLANGES ONE INTEGRAL WITH A LONGITUDINAL EDGE OF EACH OPENING, SAID FLANGES LYING IN PLANES PERPENDICULAR TO THE CYLINDER AXIS AND EXTENDING INTO THE INTERIOR OF SAID CYLINDER. 